Vacuum ring with linear bearings for an automated corneal shaper

Abstract

A medical device that can be used to cut a cornea. The device may include a blade that is coupled to a head by a blade holder. The device may also have a retention spring that exerts a force on the blade and blade holder. The head and blade can be moved across a ring by a drive assembly that contains a lead screw. The ring may contain one or more openings which have a length that is greater than a width. The openings may be coupled to a vacuum source by a tube. The vacuum pressure of the tube can be displayed by a console. The console may also have switches that allow different operating parameters to be entered through a single knob.

1. A microkeratome, comprising:
 a vacuum ring including a top surface defining an opening for receiving a cornea, a first sidewall extending from the top surface above the opening, a second sidewall extending from the top surface above the opening, at least one of the first sidewall and second sidewall having a groove, and a bore; 
 a threaded rod coupled to the vacuum ring, the threaded rod disposed along a longitudinal direction and extending into the bore; 
 a head including a linear bearing movably engaged with the groove, wherein the head is movable linearly in the longitudinal direction relative to the vacuum ring and over the opening; 
 a blade coupled to the head and movable with the head; and 
 a drive mechanism including a motor, the drive mechanism engaged with the threaded rod to move the head and the blade linearly in the longitudinal direction relative to the vacuum ring. 
 
   
   
     2. The microkeratome of  claim 1 , wherein the bore is formed in at least one of the first sidewall and second sidewall. 
   
   
     3. The microkeratome of  claim 1 , wherein the groove is a first groove formed in the first sidewall, the linear bearing is a first linear bearing movably engaged with the first groove, the second sidewall includes a second groove, and the head further includes a second linear bearing movably engaged with the second groove. 
   
   
     4. The microkeratome of  claim 1 , further including a handle enclosing the motor and attached to the head, wherein the threaded rod extends from the handle to the vacuum ring. 
   
   
     5. The microkeratome of  claim 4 , wherein the handle extends from the head at a non-zero angle relative to the top surface. 
   
   
     6. The microkeratome of  claim 1 , further including a blade holder, wherein the head has a cavity, the blade holder is disposed in the cavity, and the blade is coupled to the head via attachment of the blade to the blade holder. 
   
   
     7. The microkeratome of  claim 1 , wherein the drive mechanism is a first drive mechanism and the first drive mechanism is coupled to the threaded rod and the vacuum ring to move the head and the blade linearly in a first direction, and further including a second drive mechanism coupled to the blade to move the blade in a second direction. 
   
   
     8. The microkeratome of  claim 7 , wherein the second drive mechanism includes an eccentric cam coupled to the blade. 
   
   
     9. The microkeratome of  claim 7 , further including a handle attached to the head and enclosing the first drive mechanism and the second drive mechanism, wherein the threaded rod extends from the handle to the vacuum ring. 
   
   
     10. The microkeratome of  claim 7 , further including an input device configured to vary a speed of the first drive mechanism. 
   
   
     11. The microkeratome of  claim 7 , further including an input device configured to vary a speed of the second drive mechanism. 
   
   
     12. The microkeratome of  claim 7 , further including a first input device configured to vary a speed of the first drive mechanism and a second a input device configured to vary a speed of the second drive mechanism. 
   
   
     13. The microkeratome of  claim 1 , wherein the vacuum ring further includes a vacuum port. 
   
   
     14. A method for operating a microkeratome, the microkeratome including a vacuum ring, a head engaging the vacuum ring, a blade coupled to the head, and a drive mechanism, the method comprising:
 actuating the drive mechanism while the drive mechanism engages a threaded rod coupled to the vacuum ring, the threaded rod disposed along a longitudinal direction and extending into a bore of the vacuum ring; and 
 moving the head and the blade linearly in the longitudinal direction relative to the vacuum ring and over an opening defined by a top surface of the vacuum ring, wherein moving the head includes moving a linear bearing of the head in a groove of the vacuum ring. 
 
   
   
     15. The method of  claim 14 , wherein moving the blade cuts corneal tissue. 
   
   
     16. The method of  claim 14 , wherein the drive mechanism actuated is a first drive mechanism, and further including moving the blade in a direction transverse to the linear motion of the head and the blade by actuating a second drive mechanism coupled to a blade holder in which the blade is held. 
   
   
     17. The method of  claim 16 , further including operating a first input device to vary a speed of the first drive mechanism, and operating a second input device to vary a speed of the second drive mechanism. 
   
   
     18. The method of  claim 14 , further including drawing a vacuum through a vacuum port of the vacuum ring.